1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2004 David Schultz <das@FreeBSD.ORG> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <fenv.h> 30 #include <math.h> 31 32 /* 33 * We save and restore the floating-point environment to avoid raising 34 * an inexact exception. We can get away with using fesetenv() 35 * instead of feclearexcept()/feupdateenv() to restore the environment 36 * because the only exception defined for rint() is overflow, and 37 * rounding can't overflow as long as emax >= p. 38 * 39 * The volatile keyword is needed below because clang incorrectly assumes 40 * that rint won't raise any floating-point exceptions. Declaring ret volatile 41 * is sufficient to trick the compiler into doing the right thing. 42 */ 43 #define DECL(type, fn, rint) \ 44 type \ 45 fn(type x) \ 46 { \ 47 volatile type ret; \ 48 fenv_t env; \ 49 \ 50 fegetenv(&env); \ 51 ret = rint(x); \ 52 fesetenv(&env); \ 53 return (ret); \ 54 } 55 56 DECL(double, nearbyint, rint) 57 DECL(float, nearbyintf, rintf) 58 DECL(long double, nearbyintl, rintl) 59